What is the main advantage of the ED80-FCD100's triplet design with HOYA glass?
The air-spaced triplet objective, using HOYA FCD100 extra-low dispersion (ED) glass, provides apochromatic performance. Its primary advantage is the virtual elimination of chromatic aberration (false color). Views are sharp and high-contrast, with true-to-life color fidelity.
How does the included 0.8x reducer change the ED80-FCD100's performance for imaging?
The 0.8x reducer transforms the telescope for wide-field astrophotography. It shortens the effective focal length from 480mm to 384mm and makes the optical system "faster" by changing the focal ratio from f/6 to f/4.8. The wider field suits large nebulae, and the faster ratio needs about 36% less exposure time on extended objects.
What kind of mount do I need for the 7.5 lb Explore Scientific ED80-FCD100?
The tube weighs 7.5 lbs and has a Vixen-style dovetail. Add the weight of your camera and accessories and choose a Vixen-saddle mount whose imaging capacity comfortably exceeds the total. Explore Scientific also sells this tube and reducer as a package with its iEXOS-100-02 mount.
Can I use the Explore Scientific ED80-FCD100 for visual astronomy?
Yes, it is an excellent visual instrument. However, this bundle is configured for imaging. To use it visually, swap the 0.8x reducer for a star diagonal (Explore Scientific's package list includes a 99% reflective 2-inch diagonal) and add eyepieces, which are not included.
How do I attach my DSLR or astronomy camera to the ED80-FCD100 bundle?
The 0.8x reducer has standard male M42x0.75 T-threads. You will need a 42 mm T-ring for your camera's lens mount. It needs 55mm (+/- 2mm) of back spacing to the camera sensor. A DSLR on a standard T-ring comes close; mirrorless and astronomy cameras usually need spacers.
What is the benefit of the 2.5" hexagonal focuser on the ED80?
The 2.5" hexagonal focuser is rugged, with precise control, and is rated for imaging setups up to 10 lbs.
Is the ED80-FCD100 a good telescope for imaging the Orion Nebula (M42)?
Yes. With the 0.8x reducer, an APS-C sensor covers about 3.5 by 2.3 degrees at 384mm, so M42, M43 and the Running Man Nebula fit with room around them. The bright core needs short exposures alongside long ones to avoid saturating it.
What does "back focus" mean and why is the 55mm distance important?
Back focus (back spacing) is the required distance between the focal reducer and the camera's sensor. For the included 0.8x reducer, this distance must be 55mm (+/- 2mm). Staying within that range helps keep stars sharp toward the corners of the frame.
Is this ED80-FCD100 bundle suitable for high-magnification planetary imaging of Jupiter or Saturn?
While the ED80's optics are sharp enough for planetary viewing, its native 480mm focal length is quite short for serious planetary imaging, which usually uses much longer effective focal lengths. To increase the image scale for planets, you would add a Barlow lens (not included) in place of the reducer.
Does the Explore Scientific ED80-FCD100 come with a finder scope or case?
No finder scope or case. Explore Scientific's package list gives the telescope with its 2.5-inch focuser, two focuser extension tubes, built-in dew shield, dust cover/lens cap, Hybrid Finder Scope Base (finder scope not included), a 99% reflective 2-inch diagonal, and the 0.8x reducer with end caps and an adapter with 42 mm T2 ring thread. Eyepieces are not included.
